Answer:
<u>Option- D: </u>Is the best choice to choose from the given options.
Now, let us explain the term Cell cycle in a more comprehensive way.
<u>As the cell cycle is controlled at three checkpoints.</u>
- The integrity of the DNA is assessed at the G₁ checkpoint. 
- Proper chromosome duplication is assessed at the G₂ checkpoint. 
- Attachment of each kinetochore to a spindle fiber is assessed at the M checkpoint.
Explanation:
The cell cycle is controlled by three internal checkpoints that evaluate the condition of the genetic information.
- <u>The G₁ Checkpoint</u>:This stage determines whether all conditions are favorable for cell division to proceed. The cell can halt the cycle and attempt to remedy the problematic condition, or the cell can advance into G₀ (inactive) phase and await further signals when conditions improve.
- <u>The G₂ Checkpoint:</u> The most important role of the G₂ checkpoint is to ensure that all of the chromosomes have been accurately replicated without mistakes or damage.
- <u>The M Checkpoint:</u>It occurs near the end of the meta-phase stage of mitosis. it determines whether all the sister chromatids are correctly attached to the spindle micro-tubules
 
        
             
        
        
        
I think 
Prometer---> Spot where transcription begins 
Operator ---> On/Off switch 
Terminator ---> Spot where transcription ends 
        
                    
             
        
        
        
Answer:
B) lighting a match
Explanation:
 a chemical change is a chemical reaction involving the rearrangement of atoms. While a physical change can often be reversed, a chemically change typically cannot.
Always remember, if something is being lit on fire then it is a chemical change, since fire breaks the bonds in between the atoms. 
Freezing water is a physical change because it can be reversed and does not alter the substance, which is water. a change in state i always a physical change
tearing up a piece of paper is a physical change since nothing on a molecular level has changed. its still paper.
Dissolving sugar in water is a <em>homogenous mixture</em>, meaning that it looks uniform without, however it is still only sugar and water, so it is a physical change.
 
        
             
        
        
        
Answer:
Stop intruders from harming the body
Explanation:
 
        
                    
             
        
        
        
Answer:
It is used for lipogenesis
Explanation:
Carbohydrates are broken down into glucose and then this glucose is absorbed in the blood from where it enters the cell and used for ATP production.
The excess of glucose in the body is used for lipogenesis. So excess glucose converts into fat and stored in the liver. Some fat is also stored as glycogen in the liver and muscles by the action of insulin but the majority of excess glucose converts into fat.  
This fat provides a reserve energy source in our body. Therefore the right answer is- It is used for lipogenesis.